Compressor and lubricating means therefor



Oct. 16, 1956 E, w. RUSCH mm 2,

COMPRESSOR AND LUBRICATING MEANS THEREFOR Filed Nov. 8, 1954 IIVVENTORSI funk,

AT TORNE Y5 l mited States Pate ,1

Refrigerator Company, Greenvllle, Mich, a corporahon of MichiganApplication November 8, 1954, Serial No. 467,396

6 Claims. (Cl. 239-406) This invention relates to a compressor andlubricating means therefor. The invention is particularly useful inconnection with the application of motor compressor units adapted forcompressing or pumping fluids as, for example, for compressing a fluidused in refrigerating apparatus, such as Freon, methyl chloride, etc. Itwill be understood, however, that the invention is applicable to avariety of compressors and similar structures.

Compressors have heretofore been employed in which eccentric crank pinshave been connected with pistons and in which oil passages have been incommunication with a pool of oil in the shell of the compressor unit,the oil being moved through the passages by centrifugal pumping action.Patent No. 2,146,097, dated February 7-, 1 939, to Touborg, shows such astructure, capable of carrying the oilto a fair extent through the crankpin, but it'has beendiihcultto carry oil effectively to higher points.This difficulty has been caused, at" least in part, by the fact thatparticles of liquid refrigerant become entrained in the lubricating oiland as the oil moves up the passage, the surface of which is warmed bythe friction of the crank pin moving within the crosshead, the entrainedrefrigerant vaporizes and vapor or" gas so formed serves-to breakthe-continuity of the flowof oil in the passage, interrupting:lubrication of the moving parts.

One of the main objects of the present invention is to provide effectivemeans for lubricating the driving shaft and'the bearingsurfacesof movingparts of a compressor unit or similar structure, particularly the upperportions thereof. Another object is to' provide means for preventingvapor that may become entrained in the lubricant from interruptinglubricant flow; A- further object is to provide simple and efiicientmeans for separating vapor from the lubricant and for removing vaporfrom the lubrication: channels so' as to permit an uninte'r i up'tedflow of lubricantto the surfaces of the: moving parts?- Other specificobjects and advantages will appear asthe specification proceeds.

The invention isshown in an illustrative embodiment by the accompanyingdrawing, in which Fig; l isave'r-tical sectional'view' of a compressorunit equipped with oil-feeding means and vapor separating meansembodying our invention; Fig; 2, a broken side view inelevation of thevertical shaft: and crank pin; Fig. 3, a sectional detail view, thesection-Being taken as indicated at line 3-=3' of Fig. 2.

Within the shell is mounted a chassis or frame 12 which" maybe supportedby" a plurality of springs 13 or other means so that the lower portionof the" chassis" or frame is above the pool ofoil. Within the frame-12-is mounted a vertical shaft 14 equipped with a Weight member 15 andwith an eccentric or crank pin- 16. The crank pin" 16 is mounted withina slide member or cylindric'alf cros'shead 17 -an'd the erosshe'ad IT isslidably mounted Within the" cylindrical yoke 18: The yoke 18- is sealedor otherwise secured to a piston 19 suds-111 mount 'ice ed within acylinder 20. The piston chamber is controlled by a wafer valve 21 ofwell-known construction and the frame provides the usual inlet andoutlet passages communicating with the piston chamber. Since the frameand compressor unit structure is well-known in the art, it is believedthat a detailed description herein is unnecessary. No claim herein ismade to the compressor structure per se. The general organization andoperation of the compressor unit is set out in detail: in Touborg PatentNo. 2,146,097, which issued February 7, 1 939.

Suitable means for rotating the shaft 14 may be provided.- In theillustration given, a rotor 22' is secured to the upper end of the shaft14 andthe rotor is provided with cooling vanes 23. A stator 24- is.carried by the casing around the rotor 22.

The lower portion ofthe crank pin 16 is provided witha shortverticalpassage 44. Passage 44 extends upwards along the vertical axis of crankpin 16' and connects with a horizontal passage 29 extending to thelateral surface of the crank pin. An oil pickup tube 27, having; asubstantially uniform diameter throughoutits entire extent and formed ofheat conductive material is inserted: and secured in the verticalpassage 44, the tube being bent so that inleta28 of the pickup tube 27is substantially in alignment with the vertical axis of shaft-.14. Inthe wall of the pickup tube 27 near the base of the crank pin-16there-is asmall vent or aperture 45 directed toward and" adjacent to thevertical axis of shaft 14.

The" shaft and-its crank pin are also provided withan inclined passage31. The lower end of passage 31 is located on the surface of crank pin16 at a point opposite and slightly above the outlet of the horizontalpassage 29, and is' connected therewith by a spiral groove 29a. Theinclined passage 31 extends upwardly and terminates at o'utlet 26 in thesurface of shaft 14. From the outlet 26 of the inclined passage 31 thereextends upwardly along shaft 14' a spiral groove 30, as shown in Figs. 1and 2,.for leading'oilsupwardly about the shaft. The lower end ofpassage 31 is closer. to the'verticalaxis of shaft 14 than the" outlet26, and a portion of. the surface area of the crank pin: is flattened at33.

The inner frame-portion 1 2a" ab'out shaft 14 is preferablyprovidedne'ar' its top'witlr an overfiow'passage 34 permitting oil to befed from the top of passage" 30 through overflow passage 34- and into areceptacle 35 provided by the frame- 12. The oil Within receptacle 35flows downwardly through passage 36. Plug 41- contains an orifice 42,said orifice being of predetermined size, that connects" with thesuction chamber of the compressor and a portion ofthe" downwardlyflowing oil is drawn through this orifice. The balanceof the; oil in itsdownward flow follows the path shown in Fi 15, flowing over andlubricating the walls of the piston 19 after which the oil flows to thebottom of the shell 10'.

The'cylind'er 20may be equipped with a bracket 39 for supporting ascreen or filter 40 which extends about the inlet 28 of tube 27.

Operation In the operation of the compressor apparatus, and moreparticularly the lubricating means thereof, shaft 14 is rotated by theoperation of the rotor 22 and stator 24 and the eccentric 16 is rotated.In this operation, while the eccentric moves in a circular course,sliding the crosshead l7 back and forth and. moving the yoke 18 andpiston 1 9 back and forth; the intake portion the pickup tube 27 remainssubstantially line.- with the longitudirial axis: of shaft 14,. and.rotates in. the oil and liquid refrigerant mixture of. pool IL Since thepickup'tube extends upwardly toward the vertical'ta'xis: oficranlepinlfi and'away from the vertical axis of shaft 14, centrifugalforce produced by the rotation of the pickup tube causes fluid fromrpool11, in which intake 28 is immersed, to flow upwardly into horizontalpassage 29.. p

The liquid refrigeranttin'the oiland refrigerantmixture has a fairlylowvaporization temperature so" that the application of a small amountof'heat causes 'the a vertical axis of shaft 14. The outward pressurecreated "by the exp-anding'vapor within the tube 27 having Walls 7refrigerant to vaporize. As the fluid rises in tube 27 durof uniformdiameter, and the upward force produced by a theoil moving upwardlyunder the influence of centrifugal force, expels the vapor through vent4S. Vapor which would otherwise tend to form bubbles and vapor-lock thelubricating system is thereby discharged to allow a continuous upwardflow of oil for lubrication of the moving parts.

The oil thrown out through the passage 29 by centrifugal force movesupwardly along the groove 29a to the flat 33 and the lower end 32 of theinclined passage I 31. The flat serves as a metering device to pass a portion of the oil upwardly along the surface of the crank pin 16 andthence downwardly to lubricate the surface between the crosshe'ad l7 andthe cylindrical yoke 18. Thegreater portion of the oil is carried bycentrifugal force upwardly along the inclined passage 31, out theopening 26 and thence upwardly along the spiral groove 30. In its upwardmovemenL/the oil lubricates shaft 14.

Upon reaching the top of groove 30 the oil flows downwardly throughoverflow passage 34, thereby lubricating the frame, thence throughpassage 36 past'the plug'l in which there is an orifice 42. The pressuredifferential between the side of the orifice exposed to the'suctionchamber 43 and the opposite side of said orifice, combined with theaspirator effect of the gaseou refrigerant passing the surface of theorifice plate exposed to the suction chamber, draws a metered quantityof the downwardly flowing oil through the orifice 42 and into thesuction chamber 43 where it is picked up by 'the'refrigerant tolubricate the surfaces of the suction and discharge valves and theforward bearing surfaces of the piston 19 and cylinder'ZG. The balanceof the downwardly flowing oil passes across and lubricates the surfaceof the reciprocating piston 19 and then flows into the pool of oil atthe bottom of the compressor shell.

While the oil mechanism has been described specifically in connectionwith a' compressor unit, it will be under.- stood the invention isapplicable to other rotating devices in which it isdesired to draw oilfrom a pool upwardly through rotating parts whose surfaces are to belubricated. The lubricating area shown is, however, particularly use--ful in connection with a compressor of the construction shown. a

While in the foregoing specification we have shown a specificlubricating device in considerable detail for the purpose ofillustrating an embodiment of the invention, it will be understood thatsuch details of strusturemay be varied widely by those skilled in theart without departing from the spirit of our invention.

We claim:

1. In a compressor unit having a shell provided with a chamber adaptedto support a fluid mixture in the lower portion thereof, a substantiallyvertical shaft rotatably mounted within said shell, an eccentric crankpin provided at the lower end of said shaft, said crank pin having anupwardly extending passage at the lower por- V the 'thrust'bearingsurfaces, and into receptacle 35 in tion thereof and communicating withthe lateral surface of said crank pin at a point laterally spaced fromthe axis of said shaft, said crank pin being provided at the lowerportion thereof with a fluid pickup tube communi- V cating with saidupwardly extending passage, said pickup tube being inclined downwardlyand outwardly and toward the vertical axis of said shaft and having alower fluid intake portion substantially in alignment with the 'verticalaxis of said shaft, said pickup tube having a substantially uniformcross sectional area along its length and having a lateral aperture inthe wall of said tube a above the oil level in said compressor anddisposed toward the vertical axis of said shaft, whereby, upon rotationof said shaft and said eccentric crank pin, fluid mixture is drawnupwardly by centrifugal force into said inclined pickup tube, the densercomponents of said mixture passing through said tube into said upwardlyextending passage and the lighter components of said fluid mixture beingforced through said lateral aperture.

2. The structure of claim 1, 'whi h said crank pin has an inclinedpassage having an upper outlet in the surface of said shaft and a lowerinlet in the surface of said crank pin, said lower inlet of saidinclined passage being in general alignment with the vertical axis ofsaid 'shaft, said crank pin also having a peripheral groovecornmunicating with the lower inlet of said inclined passage and withsaid upwardly extending passage.

3. In a compressor unit having a shell provided with a chamber adaptedto support a'fiuid mixture in the lower portion thereof, a substantiallyvertical shaft rotatably mounted within said shell, an eccentric crankpin provided at the lower end of said shaft, said crank pin having anupwardly extending passage at the lower portion thereof and having anoutwardly extending passage communicating with the upper end of saidupwardly extending passage and with the lateral surface of said crankpin, said crank pin being provided at the lower portion thereof 1 with afluid pickup tube communicating with said upwardly extending passage andhaving an inclined passage provided with an'outlet on the surface ofsaid shaft and with a lower inlet on the surface of said crank pinsubstantially in alignment with the vertical axis of said shaft, saidpickup tube being inclined downwardly andoutwardly and toward the axisof said shaft and having a lower fluid intake portion substantially inalignment with the vertical axis of said shaft, said pickup tube havinga substantially uniform cross sectional area along its length andhavinga lateral aperture in the wall of said tube disposed toward and adjacentto the vertical axis of said shaft, said crank pin having a peripheralgroove communicating with the lowerl inlet of said inclined passage andwith said outwardly extending passage, and said shaft having a spiralperipheral groove communicating with'the outlet of said inclined passageon the surface of said shaft.

4. ha structure of the characterrset'forth, a shell providing a' chamberadapted to support ;a lubrication mixture in the lower portion thereof,an inner frame supported within said shell, a substantially verticalshaft rotatably mounted in said frame and provided with -an eccentriccrank pin at the'lower end thereof, a cylinder rigid with said framehaving a piston movably'mounted ,therein, and a driving connectionbetween said crank pin surface of said crank pin, the lower inletportion of said intaketube being immersed in the lubrication mixture inthe lower portion of the chamber so that centrifugal action causesthe-lubrication mixture to flow upwardly in said intake tube when saidshaft and crank pin are rotated,

and said intake tube; having asubstantially uniform cross sectional areaalong its length and having a lateral aperture in the wall of said tubedisposed toward the vertical axis of said shaft for the escape of vapordisplaced from said lubrication mixture.

5. The structure of claim 4, in which said crank pin has an upperinclined passage therein terminating on the lateral surface of saidshaft and having an inlet on the lateral surface of said pin above anddiametrically opposite the outlet of said lower passage, and means forproviding a flow of lubricant from the outlet of said lower passage tothe inlet of said inclined passage.

6. In a structure of the character set forth, a shell providing achamber adapted to support a lubrication mixture in the lower portionthereof, a substantially vertical shaft rotatably mounted in said shelland provided with an eccentric crank pin at the lower end thereof, saidcrank pin being provided at the lower portion thereof with a downwardlyand outwardly extending intake tube having a lower inlet portionsubstantially in alignment with the axis of said shaft, said crank pinbeing provided with a lower passage therethrough communicating with theupper portion of said intake tube and terminating in an outlet on thelateral surface of said crank pin, said crank pin having an upperinclined passage therein terminating on the lateral surface of saidshaft and having an inlet on the lateral surface of said crank pin aboveand diametrically opposite the outlet of said lower passage, said crankpin also being flattened about the inlet of said inclined passage, meansfor providing a flow of lubricant from the outlet of said lower passageto the inlet of said inclined passage, and said intake tube having asubstantially uniform cross sectional area along its length and having alateral aperture in the wall thereof directed toward the vertical axisof said shaft for the escape of vapor from said lubrication mixture.

References Cited in the file of this patent UNITED STATES PATENTS2,146,097 Touborg Dec. 16, 1937 2,287,203 Smith Sept. 29, 1939 FOREIGNPATENTS 871,115 France May 28, 1941

